I really don't know
Why did he take this leak and print it? Can he be trying to passively aggressively destroy the white house? He knew better than to leak this out. Even if Valerie Plame was a janitor, you don't leak out CIA agents identities, even if the request not to do so was mild.
He is dissembling on Valerie Plame's status. 3 networks now have stated that she ran informants, and that the CIA is checking the damage. So, it gets muddled. The sense I can make of it is that Plame used to run informants under cover as the ambassador's wife, but has now shifted to work as an analyst. She may not have assets now, but she could have assets from 5-10 years ago who would be nervous about this leak.
Who did the leak benefit? The democrats. Novak shouldn't have agreed to do the leak, because it could only cause blowback. I am now of the opinion that Rove was not involved at all, but it was a 28 year old jackass who thought he was going to play Nixon plumber squad. The 6 other reporters realized the person was being an ass, and refused to report this for national security reasons, as well as the anger of the White House for printing something so stupid with no side benefits.
Further Novak is damaging the White House further with his purposeful evasions. He could let people know that no "professional" was involved, but is using his reporter source shield to actually make the story worse.
Somebody not to bright was the person to talk to Novak, and Rove has never been accused of that crime.